What is ADJECTIVE?

An adjective modifies a noun or a pronoun by describing, identifying, or quantifying words. An adjective usually precedes the noun or the pronoun which it modifies.

Examples:

The apartment is new.

I have an adorable little sister.

The school compound is clean.

Degrees of Adjectives

The degrees of comparison are known as the positive, the comparative, and the superlative.

The comparative is used to compare two things. The suffix "-er" is added to adjective to form most of the comparatives. Sometimes, the word "more" or "less" precedes an adjective to show comparative. After the comparative, the word "than" is added.

The superlative is used to compare three or more things. The suffix "-est" is added to adjective to form most of the superlatives. The word "most" or "least" precedes an adjective to show superlative. Before the superlative, the article "the" is added.

Positive	Comparative	Superlative
Big	Bigger	Biggest
Small	Smaller	Smallest
Tall	Taller	Tallest
Delicious	More delicious	Most delicious
Beautiful	More beautiful	Most beautiful
Colourful	More colourful	Most colourful

Examples:

I am tall. (positive)

Ali is taller than me. (comparative)

Abu is the tallest among us. (superlative)

Alice's dress is beautiful. 

Briana's dress is more beautiful than Alice's. 

Claire's dress is the most beautiful dress among them.

(Adapted: http://grammar.ccc.commnet.edu/grammar/adjectives.htm ; http://www.writingcentre.uottawa.ca/hypergrammar/adjectve.html )